What Causes Pharyngitis?

Patient Presentation
A 7-year-old male came to clinic with a 4 day history of a sore throat. His mother reports that he also had some voice changes like laryngitis and some mild croupy sounding cough. That morning he came to the kitchen for breakfast crying almost inconsolably because he was in so much pain. He had been going to school and there was strep throat circulating in the community. He also had been taking ibuprofen with some relief. The past medical history was non-contributory and his immunizations were current. The review of systems revealed no fever, chills, rhinorrhea, ear pain, headache, muscle ache, abdominal pain or rash.

The pertinent physical exam showed a slightly tired appearing male who was afebrile and had normal growth parameters. He had a laryngitic sounding voice. HEENT examination revealed erythematous tonsils without exudates. There was no palatal petechiae, but pinpoint vesicles on the soft palate were seen. There was no deviation of the tonsillar pillars. His ears and nose were normal. He had shoddy anterior cervical adenopathy. The rest of his examination was negative. The laboratory evaluation included a rapid streptococcal antigen test that was negative. The throat culture eventually was negative. The diagnosis of viral pharyngitis/laryngitis was made and appropriate instructions were given to the family.

Sore throat caused by group A, beta-hemolytic streptococcus (GAS) is classically characterized as a patient with a constellation of various symptoms including fever, headache, emesis, sore throat, palatal petechiae, abdominal pain, sand-papery skin rash and often with a history of close contact. The rapidity of onset is relatively short but generally not characterized as rapid. Patients with upper respiratory tract symptoms or allergic symptoms including rhinitis, conjunctivitis, voice changes (e.g. raspy, croupy, laryngitic) tend to have viral etiologies for their sore throat. Differentiating between viral pharyngitis and GAS is a common conundrum. Rapid antigen testing and throat cultures assist in making the proper diagnosis, so that nonsupprative complications such as acute rheumatic fever or acute glomerulonephritis can be avoided. Serotypes 1,6, and 12 of GAS are associated with these sequelae. Rapid onset of fever, difficulty swallowing, drooling, voice change (particularly muffled or hot-potato), respiratory distress and toxicity may indicate retropharyngeal abscess, peritonsillar abscess, tonsillar hypertrophy caused by Epstein-Barr virus, or epiglottitis. An immunization history should help determine if a patient is at risk for Diphtheria or Haemophilus influenza type b. A careful sexual history of oral-genital contact should be obtained in tweens, teens and young adults looking for the possibility of a sexually transmitted infection.

Learning Point
The differential diagnosis of sore throat includes:

  • Infectious
    • Viral
      • Adenovirus
      • Coxsackie virus
      • Echovirus
      • Epstein-Barr virus
      • Herpes simplex
    • Bacterial
      • Streptococcus, group A, beta-hemolytic
      • Streptococcus, groups B, C and G, beta-hemolytic
      • Streptococcal pneumoniae
      • Staphylococcus aureus
      • Arcanobacterium haemolyticum
      • Chlamydia trachomatis
      • Corynebacterium diphheriae
      • Haemophilus influenza type b
      • Mycoplasma pneumoniae
      • Neisseria gonorrhea
      • Tularemia
    • Fungal
      • Candida albicans
  • Miscellaneous
    • Epiglottitis
    • Kawasaki disease
    • Peritonsillar abscess
    • Retropharyngeal abscess
    • Post-nasal drip (allergic, upper respiratory infection)
    • Tobacco
    • Trauma
    • Referred pain (lymphadenitis, otitis media)

    Questions for Further Discussion
    1. List clinical presentations of group A, beta-hemolytic streptococcus.
    2. List the phylogeny of streptoccus species.
    3. What are indications for surgical consultation for pharyngitis?

    Related Cases

      Symptom/Presentation: Pain

    To Learn More
    To view pediatric review articles on this topic from the past year check PubMed.

    Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

    Information prescriptions for patients can be found at MedlinePlus for these topics: Sore Throat and Viral Infections and at Pediatric Common Questions, Quick Answers for this topic: Strep Throat

    To view current news articles on this topic check Google News.

    To view images related to this topic check Google Images.

    Woodhead JC. Pediatric Clerkship Guide. Mosby. St. Louis MO, 2003:306-08.

    Inkelis, SH. Sore Throat. in Pediatrics a Primary Care Approach. Berkowitz CD, ed. W.B. Saunders company, Philadelphia, PA. 1996;186-191.

    American Academy of Pediatrics. Group A Streptococcal Infections, In Pickering LD, Baker CJ, Kimberlin DW, Long SS, eds. Red Book: 2009 Report of the Committee on Infectious Diseases. 28th edit. Elk Grove Village, IL: American Academy of Pediatrics; 2009;616-628.

    ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effectively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients’ is gathered.
    4. Patient management plans are developed and carried out.
    7. All medical and invasive procedures considered essential for the area of practice are competently performed.
    8. Health care services aimed at preventing health problems or maintaining health are provided.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

  • Practice Based Learning and Improvement
    13. Information about other populations of patients, especially the larger population from which this patient is drawn, is obtained and used.


    Donna M. D’Alessandro, MD
    Professor of Pediatrics, University of Iowa Children’s Hospital